Backfires!

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e30_Turbo
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Post Wed Mar 19, 2008 12:37 pm

Is it a ignition only thing?

Can anything cause backfires during cranking?

I can bring them on without issue with the spark cut rev limiter I use, set it to 4k, slam pedal to the floor and I get 2 foot flames and a WRC style popping going on, which is nice, although the natives are getting a little annoyed these days.

Just wondered if there was anything else that was known to cause these......

Thanks, Mark.
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Jhonno
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Post Wed Mar 19, 2008 7:18 pm

on throttle or off?
Got cable ties? Get diffin..

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blingsta
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Post Thu Mar 20, 2008 10:19 am

overfuelling? leaking injector?
ShepsEvo3
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Post Thu Mar 20, 2008 7:16 pm

fozzymonster wrote:set it to 4k, slam pedal to the floor and I get 2 foot flames and a WRC style popping going on, which is nice
:cool:
E30 M3 Unichip Alpha N style conversions, this is the ultimate for extracting the best out of your S14 M power car.
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ShepsEvo3
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Post Thu Mar 20, 2008 7:17 pm

Have you got a leaky exhaust? excess fuel into a hot exhaust which is also drawing in air can cause these sort of things too :wink:
E30 M3 Unichip Alpha N style conversions, this is the ultimate for extracting the best out of your S14 M power car.
Also, Live mapping of your Standard Motronic ECU for optimising all your modifications.
www.sabre-tuning.co.uk
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siddiqi1
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Post Thu Mar 20, 2008 10:18 pm

Is it a ignition only thing?

Can anything cause backfires during cranking?

I can bring them on without issue with the spark cut rev limiter I use, set it to 4k, slam pedal to the floor and I get 2 foot flames and a WRC style popping going on, which is nice, although the natives are getting a little annoyed these days.

Just wondered if there was anything else that was known to cause these......

Thanks, Mark.
why you complaining, i owuld die for that

do you have a turbo buddy?
Turbo-Brown
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Post Thu Mar 20, 2008 10:34 pm

Hey Mark, when you say backfires, what's happening when you're cranking the motor dude?

What's your cranking advance set to?
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agreen
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Post Thu Mar 20, 2008 11:31 pm

2 foot flames , why change it 8)
suzie650
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Post Fri Mar 21, 2008 12:02 am

agreen wrote:2 foot flames , why change it 8)
because you get sick of patching your backbox after a while...

Does it happen under load as well?
e30_Turbo
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Post Mon Mar 24, 2008 3:05 pm

Turbo-Brown wrote:Hey Mark, when you say backfires, what's happening when you're cranking the motor dude?

What's your cranking advance set to?
They're so random I'm thinking I have a timing issue, some gremlin giving me random sparks.

Cranking advance is set to 10 deg and I've gone up to 15 but no better, 10 works best, when it works.

It's just so un-reliable, starts in key only one day, next day it's not starting at all, I feel I'm chasing something I've not found as yet.

I did notice my cranking voltages have dropped again, I wonder if the battery is fucked also....... charges ok tho......

Sometimes after a few mins turning over the backfire is right after the key is turned back...which is strange again.

What's everyone using on MS for cranking PW? IIRC I had luck with 2ms around 4c.

Thanks, Mark
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e30_Turbo
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Post Mon Mar 24, 2008 4:33 pm

siddiqi1 wrote: why you complaining, i owuld die for that

do you have a turbo buddy?
Yes I do, just a little snail tho :cool:
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e30_Turbo
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Post Mon Mar 24, 2008 4:39 pm

ShepsEvo3 wrote:Have you got a leaky exhaust? excess fuel into a hot exhaust which is also drawing in air can cause these sort of things too :wink:
Well it's not airtight but the downpipe is welded up and the push joints are only from the mid section back.

I'll pull the turbo off and check that all is well round the gaskets, manifold/head - manifold/turbo - turbo/downpipe etc

It doesn't backfire during running or under load, just when cranking and not starting.

I've tried everything from no fuel to more than it could ever use and pulled timing eitherway, made sure no enrichments are on and even tried to trim the cranking value.

It's the fact it seems to be a different issue each day that' driving me mad, upto Sat this week it would start on the turn of the key and kinda warm up itself, which took me a few hours or setting up, now tho it won't even start! fecking thing......ebay soon lol
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Colonel Sanders
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Post Mon Mar 24, 2008 5:10 pm

you got your new engine in yet mark??
alex-e30
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Post Mon Mar 24, 2008 5:16 pm

you havent accidently put a diesel additive in the tank have you?

8)
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Jhonno
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Post Mon Mar 24, 2008 6:28 pm

siddiqi1 wrote:
Is it a ignition only thing?

Can anything cause backfires during cranking?

I can bring them on without issue with the spark cut rev limiter I use, set it to 4k, slam pedal to the floor and I get 2 foot flames and a WRC style popping going on, which is nice, although the natives are getting a little annoyed these days.

Just wondered if there was anything else that was known to cause these......

Thanks, Mark.
why you complaining, i owuld die for that

do you have a turbo buddy?
seriously?! :roll:
Got cable ties? Get diffin..

Arch roller for hire.

www.zeroexhausts.co.uk

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siddiqi1
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Post Mon Mar 24, 2008 9:33 pm

fozzymonster wrote:
siddiqi1 wrote: why you complaining, i owuld die for that

do you have a turbo buddy?
Yes I do, just a little snail tho :cool:
So so soooooooooooo jealous! But god on ya fella, good on ya!

Hope you solve the problem asap, Ill be asking you what you did to correct it, and doing the COMPLETE OPPOSITE to bang out some flames!
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siddiqi1
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Post Mon Mar 24, 2008 9:36 pm

Jhonno wrote:
siddiqi1 wrote:
Is it a ignition only thing?

Can anything cause backfires during cranking?

I can bring them on without issue with the spark cut rev limiter I use, set it to 4k, slam pedal to the floor and I get 2 foot flames and a WRC style popping going on, which is nice, although the natives are getting a little annoyed these days.

Just wondered if there was anything else that was known to cause these......

Thanks, Mark.
why you complaining, i owuld die for that

do you have a turbo buddy?
seriously?! :roll:

Comeon, you dont think thats cool, coming from an E30. comonnnnnnnnnnnnnn